WO2018003312A1

WO2018003312A1 - Semiconductor processing sheet

Info

Publication number: WO2018003312A1
Application number: PCT/JP2017/017966
Authority: WO
Inventors: 優智中村; 尚哉佐伯; 小野　義友
Original assignee: リンテック株式会社
Priority date: 2016-06-30
Filing date: 2017-05-12
Publication date: 2018-01-04
Also published as: JP2022058712A; TWI750171B; KR20190022444A; CN109075048A; KR20230066116A; TWI782802B; JP7336548B2; TW201803042A; KR102528636B1; TW202211394A; JPWO2018003312A1

Abstract

A semiconductor processing sheet comprising at least a base material, wherein: the semiconductor processing sheet has a recovery rate of not less than 70% and not more than 100%; or the ratio of a 100% stress measured in an MD direction of the base material at 23°C to the 100% stress measured in a CD direction of the base material at 23°C is not less than 0.8 and not more than 1.2; or the tensile elasticity measured in the MD direction and the CD direction of the base material at 23°C is in each case not less than 10 MPa and not more than 350 MPa, the 100% stress measured in the MD direction and the CD direction of the base material at 23°C is in each case not less than 3 MPa and not more than 20 MPa, and the rupture elongation measured in the MD direction and the CD direction of the base material at 23°C is in each case not less than 100%. The semiconductor processing sheet can be greatly stretched, allowing semiconductor chips to be moved apart from each other sufficiently.

Description

Semiconductor processing sheet

The present invention relates to a sheet for semiconductor processing, and preferably relates to a sheet for semiconductor processing used to increase the interval between a plurality of semiconductor chips.

In recent years, electronic devices are becoming smaller, lighter, and more functional. Semiconductor devices mounted on electronic devices are also required to be smaller, thinner, and higher in density. A semiconductor chip may be mounted in a package close to its size. Such a package may be referred to as a chip scale package (CSP). One of CSPs is a wafer level package (Wafer Level Package; WLP). In WLP, before dicing into individual pieces, external electrodes and the like are formed on the wafer, and finally the wafer is diced into individual pieces. As WLP, there are a fan-in type and a fan-out type. In a fan-out type WLP (hereinafter sometimes abbreviated as “FO-WLP”), a semiconductor chip is covered with a sealing member so as to be an area larger than the chip size. Then, the rewiring layer and the external electrode are formed not only on the circuit surface of the semiconductor chip but also on the surface region of the sealing member.

For example, in Patent Document 1, for a plurality of semiconductor chips separated from a semiconductor wafer, an extended wafer is formed by surrounding the periphery using a molding member, leaving a circuit formation surface, and in a region outside the semiconductor chip. A method for manufacturing a semiconductor package formed by extending a rewiring pattern is described. In the manufacturing method described in Patent Document 1, before enclosing a plurality of individual semiconductor chips with a mold member, the semiconductor chip is replaced with an expandable wafer mount tape, and the wafer mount tape is spread to expand the plurality of semiconductor chips. The distance between them is expanding.

International Publication No. 2010/058646

In the FO-WLP manufacturing method as described above, the semiconductor chips need to be sufficiently separated from each other in order to form the above-described rewiring pattern or the like in a region outside the semiconductor chip.

This invention is made | formed in view of the above actual conditions, and provides the semiconductor processing sheet which can be extended | stretched large suitable for the use which needs to fully space | separate semiconductor chips. Objective.

In order to achieve the above object, first, the present invention provides a semiconductor processing sheet having at least a base material, wherein the recovery rate of the semiconductor processing sheet is 70% or more and 100% or less, and the restoration is performed. In the test piece obtained by cutting the semiconductor processing sheet into 150 mm × 15 mm, both ends in the length direction are gripped with a gripping tool so that the length between the gripping tools is 100 mm, and then the length between the gripping tools is measured. Is pulled at a speed of 200 mm / min until the length becomes 200 mm, and is held for 1 minute in a state where the length between the grips is expanded to 200 mm, and then 200 mm until the length between the grips reaches 100 mm. Return to the length direction at the speed, hold for 1 minute with the length between the grippers returned to 100 mm, then pull in the length direction at a speed of 60 mm / min to measure the tensile force. The length between grips when the value indicates 0.1 N / 15 mm is measured, and the length obtained by subtracting the length of 100 mm between the initial grips from the length is defined as L2 (mm). When the length obtained by subtracting the length of 100 mm between the initial gripping tools from the length of 200 mm between the gripping tools in the state of being taken as L1 (mm), the following formula (I)
Restoration rate (%) = {1− (L2 ÷ L1)} × 100 (I)
A semiconductor processing sheet characterized in that the value is calculated from the above (Invention 1).

According to the said invention (invention 1), it becomes possible to extend | stretch largely because a restoration rate is the said range. Therefore, for example, it can be suitably used for applications where semiconductor chips need to be sufficiently separated from each other, such as in the manufacture of FO-WLP.

Secondly, the present invention is a semiconductor processing sheet comprising at least a base material, wherein the base material at 23 ° C. is 100% stress of the semiconductor processing sheet measured in the CD direction of the base material at 23 ° C. The ratio of 100% stress of the semiconductor processing sheet measured in the MD direction is 0.8 or more and 1.2 or less, and the 100% stress is obtained by cutting the semiconductor processing sheet into 150 mm × 15 mm. In the test piece, both ends in the length direction are gripped by the grip so that the length between the grips is 100 mm, and then pulled in the length direction at a speed of 200 mm / min, and the length between the grips is 200 mm. Provided is a sheet for semiconductor processing, characterized in that it is a value obtained by dividing the measured value of the tensile force at that time by the cross-sectional area of the sheet for semiconductor processing (Invention 2).

According to the above invention (Invention 2), when the ratio of 100% stress is in the above range, the film can be stretched greatly. Therefore, for example, it can be suitably used for applications where semiconductor chips need to be sufficiently separated from each other, such as in the manufacture of FO-WLP.

Third, the present invention is a semiconductor processing sheet comprising at least a base material, and the tensile modulus of the semiconductor processing sheet measured in the MD direction and the CD direction of the base material at 23 ° C. is 10 MPa or more, respectively. 350 MPa or less, and 100% stress of the semiconductor processing sheet measured in the MD direction and CD direction of the base material at 23 ° C. is 3 MPa or more and 20 MPa or less, respectively. In a test piece obtained by cutting a processing sheet into a size of 150 mm × 15 mm, both ends in the length direction are gripped with a grip so that the length between the grips is 100 mm, and then pulled in the length direction at a speed of 200 mm / min. Then, divide the measured value of the tensile force when the length between grips is 200 mm by the cross-sectional area of the semiconductor processing sheet. The breaking elongation of the semiconductor processing sheet measured in the MD direction and CD direction of the base material at 23 ° C. is 100% or more, respectively. (Invention 3).

According to the said invention (invention 3), it becomes possible to extend | stretch largely because a tensile elasticity modulus and breaking elongation are the said ranges. Therefore, for example, it can be suitably used for applications where semiconductor chips need to be sufficiently separated from each other, such as in the manufacture of FO-WLP.

In the above inventions (Inventions 1 to 3), it is preferable to further comprise an adhesive layer laminated on at least one surface of the substrate (Invention 4).

In the above inventions (Inventions 1 to 4), the substrate preferably contains a thermoplastic elastomer (Invention 5).

In the above invention (Invention 5), the thermoplastic elastomer is preferably a urethane elastomer (Invention 6).

In the above inventions (Inventions 1 to 6), the semiconductor processing sheet is used to increase the interval between adjacent semiconductor chips in a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet to 200 μm or more and 6000 μm or less. Is preferable (Invention 7).

In the above inventions (Inventions 1 to 7), a semiconductor processing sheet is provided by applying tension in the four directions of the + X axis direction, the −X axis direction, the + Y axis direction, and the −Y axis direction of the X axis and Y axis perpendicular to each other It is preferably used to widen the interval between a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet by extending the length (Invention 8).

In the above inventions (Inventions 1 to 8), the step of providing a plurality of individual semiconductor chips on one side of the pressure-sensitive adhesive sheet, and the step of extending the pressure-sensitive adhesive sheet to widen the interval between the plurality of semiconductor chips Is preferably used as the pressure-sensitive adhesive sheet (Invention 9).

In the above inventions (Inventions 1 to 9), it is preferably used for manufacturing a fan-out type semiconductor wafer level package (Invention 10).

The semiconductor processing sheet according to the present invention can be stretched greatly, and the semiconductor chips can be sufficiently separated from each other.

It is sectional drawing explaining the 1st aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 1st aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 1st aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 2nd aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 2nd aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 2nd aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is sectional drawing explaining the 2nd aspect of the usage method of the sheet | seat for semiconductor processing which concerns on one Embodiment of this invention. It is a top view explaining the biaxial stretching expand apparatus used in the Example.

Hereinafter, embodiments of the present invention will be described.
The semiconductor processing sheet according to the present embodiment is configured to include at least a base material.

The restoration rate of the semiconductor processing sheet according to the present embodiment is preferably 70% or more and 100% or less.
In the present specification, the restoration rate is calculated as follows. First, a semiconductor processing sheet is cut out to 150 mm × 15 mm to obtain a test piece. The cutting is performed so that the MD direction of the base material in the semiconductor processing sheet matches the length direction of the test piece. Next, the both ends in the length direction of the test piece are grasped with the grasping tool so that the distance between the grasping tools is 100 mm. The length between the grips at this time is defined as a length L0 (mm) between the initial grips. Next, the length between the grips is pulled in the length direction at a speed of 200 mm / min, and is held for 1 minute in a state where the distance between the grips is 200 mm. The length obtained by subtracting the length L0 (mm) (that is, 100 mm) between the initial grippers from the length between the grips after being expanded to 200 mm is defined as an expansion length L1 (mm) (= 100 mm). After holding for 1 minute, the length between the grips is returned at a speed of 200 mm / min, and is held for 1 minute with the distance between the grips being 100 mm (ie, L0 (mm)). Thereafter, the length between the grips is pulled in the length direction at a speed of 60 mm / min, and the length between the grips when the measured value of the tensile force indicates 0.1 N / 15 mm is recorded. L2 (mm) is obtained by subtracting the length L0 (mm) between the initial grippers from the length. By applying the values of L1 and L2 obtained as described above to the following formula (I), the restoration rate (%) can be obtained.
Restoration rate (%) = {1− (L2 ÷ L1)} × 100 (I)
In this tensile test, the thickness of the test piece is not particularly limited, and may be the same as the thickness of the semiconductor processing sheet to be tested. Moreover, the specific measuring method is as showing in the test example mentioned later.

Moreover, in the semiconductor processing sheet according to the present embodiment, for semiconductor processing measured in the MD direction of the substrate at 23 ° C. with respect to 100% stress of the semiconductor processing sheet measured in the CD direction of the substrate at 23 ° C. The ratio of 100% stress of the sheet is preferably 0.8 or more and 1.2 or less. Here, the MD direction refers to the flow direction during manufacture of the substrate, and the CD direction refers to a direction perpendicular to the MD direction.

In this specification, 100% stress means the one calculated as follows. In a test piece obtained by cutting a semiconductor processing sheet into 150 mm × 15 mm, hold both ends in the length direction with a grip so that the distance between grips is 100 mm, and pull in the length direction at a speed of 200 mm / min. By dividing the 100% strength expressed as the strength of tensile force (measured value of tensile force) when the length of the sheet becomes 200 mm by the cross-sectional area of the semiconductor processed sheet, 100% stress (MPa) is obtained. can get. The cutting is performed so that the flow direction (MD direction) or the direction orthogonal to the MD direction (CD direction) during the manufacture of the semiconductor processing sheet coincides with the length direction of the test piece. In this tensile test, the thickness of the test piece is not particularly limited, and may be the same as the thickness of the semiconductor processing sheet to be tested. Moreover, the specific measuring method is as showing in the test example mentioned later.

Further, in the semiconductor processing sheet according to the present embodiment, the tensile modulus of the semiconductor processing sheet measured in the MD direction and the CD direction of the base material at 23 ° C. is 10 MPa or more and 350 MPa or less, respectively. 100% stress of the semiconductor processing sheet measured in the MD direction and CD direction of the substrate is 3 MPa or more and 20 MPa or less, respectively, and the semiconductor processing is measured in the MD direction and CD direction of the substrate at 23 ° C. It is preferable that the breaking elongation of each sheet is 100% or more.

The semiconductor processing sheet according to the present embodiment has the above-described physical properties, so that the semiconductor processing sheet can be easily stretched without causing breakage.

In particular, when the restoration rate is in the above range, it means that the semiconductor processing sheet is easily restored even after being largely stretched. In general, when a sheet having a yield point is stretched beyond the yield point, the sheet undergoes plastic deformation, and a portion where plastic deformation has occurred, that is, an extremely stretched portion is unevenly distributed. If the sheet in such a state is further stretched, the expanded portion becomes non-uniform even if the above extremely stretched portion breaks or does not break. In addition, in the stress-strain diagram in which the strain is plotted on the x-axis and the elongation is plotted on the y-axis, the slope dx / dy does not take a stress value that changes from a positive value to 0 or a negative value, and a clear yield point. Even if the sheet does not show, the sheet undergoes plastic deformation as the tensile amount increases, and similarly, the sheet breaks or the expansion becomes non-uniform. On the other hand, when elastic deformation occurs instead of plastic deformation, the sheet can be easily restored to its original shape by removing the stress. Therefore, when the restoration rate, which is an index indicating how much to restore after 100% elongation, which is a sufficiently large tensile amount, is in the above range, the plastic deformation of the film is minimized when the semiconductor processing sheet is stretched greatly. It is suppressed to the limit, and breakage hardly occurs, and uniform expansion is possible.

Further, when the ratio of 100% stress is within the above range, and when the tensile modulus, 100% stress and breaking elongation are as described above, the semiconductor processing sheet is stretched in the MD direction and CD direction of the substrate. In this case (hereinafter, such stretching may be referred to as “biaxial stretching”), it is difficult to cause breakage and it is possible to stretch the film greatly.

In the semiconductor processing sheet as described above, specifically, the semiconductor chips can be separated until the distance between the semiconductor chips reaches 200 μm or more. Such a semiconductor processing sheet can be suitably used in a method for manufacturing a semiconductor device that requires a sufficiently wide interval between semiconductor chips, such as a method for manufacturing FO-WLP.

1. Physical properties of semiconductor processing sheet, etc. In the semiconductor processing sheet according to the present embodiment, the restoration rate is preferably 70% or more, particularly preferably 80% or more, and more preferably 85% or more. preferable. The restoration rate is preferably 100% or less. When the restoration rate is in the above range, the semiconductor processing sheet can be greatly stretched as described above.

In the semiconductor processing sheet according to the present embodiment, the semiconductor processing sheet measured in the MD direction of the substrate at 23 ° C. with respect to 100% stress of the semiconductor processing sheet measured in the CD direction of the substrate at 23 ° C. The ratio of 100% stress is preferably 0.8 or more, particularly preferably 0.83 or more, and more preferably 0.85 or more. The ratio is preferably 1.2 or less, particularly preferably 1.17 or less, and more preferably 1.15 or less. When the ratio of 100% stress is within the above range, the semiconductor processing sheet breaks even when stress is easily applied only in a specific direction, such as when the semiconductor processing sheet is biaxially stretched. Is suppressed. As a result, the semiconductor processing sheet can be stretched more greatly.

In the semiconductor processing sheet according to the present embodiment, the breaking elongation of the semiconductor processing sheet measured in the CD direction of the base material at 23 ° C. is preferably 100% or more, particularly 150% or more. Preferably, it is preferably 200% or more. The breaking elongation is preferably 1200% or less, and particularly preferably 1000% or less. When the breaking elongation is in the above range, the semiconductor processing sheet can be greatly stretched in the CD direction of the substrate. The method for measuring the breaking elongation in the CD direction is as shown in the test examples described later.

In the semiconductor processing sheet according to the present embodiment, the breaking elongation of the semiconductor processing sheet measured in the MD direction of the base material at 23 ° C. is preferably 100% or more, particularly 150% or more. Preferably, it is preferably 200% or more. The breaking elongation is preferably 1200% or less, and particularly preferably 1000% or less. When the breaking elongation is within the above range, the semiconductor processing sheet can be greatly stretched in the MD direction of the base material. In addition, the measuring method of the breaking elongation of MD direction is as showing to the test example mentioned later.

In the semiconductor processing sheet according to the present embodiment, the tensile modulus of the semiconductor processing sheet measured in the CD direction of the base material at 23 ° C. is preferably 10 MPa or more, particularly preferably 20 MPa or more, Further, it is preferably 25 MPa or more. The tensile elastic modulus is preferably 350 MPa or less, particularly preferably 300 MPa or less, and further preferably 250 MPa or less. When the tensile elastic modulus is 10 MPa or more, when a semiconductor chip or the like is laminated on the semiconductor processing sheet, the semiconductor chip or the like can be favorably supported. In addition, when the tensile elastic modulus is 350 MPa or less, the semiconductor processing sheet has moderate flexibility, and the semiconductor processing sheet can be more easily stretched. In addition, the measuring method of the said tensile elasticity modulus is as showing to the test example mentioned later.

In the semiconductor processing sheet according to the present embodiment, the tensile modulus of the semiconductor processing sheet measured in the MD direction of the substrate at 23 ° C. is preferably 10 MPa or more, particularly preferably 20 MPa or more, Further, it is preferably 25 MPa or more. The tensile elastic modulus is preferably 350 MPa or less, particularly preferably 300 MPa or less, and further preferably 250 MPa or less. When the tensile elastic modulus is 10 MPa or more, when a semiconductor chip or the like is laminated on the semiconductor processing sheet, the semiconductor chip or the like can be favorably supported. In addition, when the tensile elastic modulus is 350 MPa or less, the semiconductor processing sheet has moderate flexibility, and the semiconductor processing sheet can be more easily stretched. In addition, the measuring method of the said tensile elasticity modulus is as showing to the test example mentioned later.

In the semiconductor processing sheet according to the present embodiment, the 100% stress of the semiconductor processing sheet measured in the CD direction of the substrate at 23 ° C. is preferably 3 MPa or more, particularly preferably 5 MPa or more, Furthermore, it is preferable that it is 6 MPa or more. When the 100% stress is 3 MPa or more, even if the thickness of the base material is reduced by greatly stretching the semiconductor processing sheet, the force necessary to support the separated chips can be maintained. It becomes possible. The 100% stress is preferably 20 MPa or less, particularly preferably 18 MPa or less, and more preferably 16 MPa or less. When the breaking elongation is 20 MPa or less, it is possible to greatly stretch the semiconductor processing sheet without imposing an excessive load on the expanding device. Even if the device is used continuously over a long period of time, the device fails. Can be expected to prevent. The method for measuring 100% stress in the CD direction is as shown in the test examples described later.

In the semiconductor processing sheet according to the present embodiment, the 100% stress of the semiconductor processing sheet measured in the MD direction of the substrate at 23 ° C. is preferably 3 MPa or more, particularly preferably 5 MPa or more, Furthermore, it is preferable that it is 6 MPa or more. When the 100% stress is 3 MPa or more, even if the thickness of the base material is reduced by greatly stretching the semiconductor processing sheet, the force necessary to support the separated chips can be maintained. This makes it possible to greatly stretch the semiconductor processing sheet in the CD direction of the substrate. The 100% stress is preferably 20 MPa or less, particularly preferably 18 MPa or less, and more preferably 16 MPa or less. When the breaking elongation is 20 MPa or less, it is possible to greatly stretch the semiconductor processing sheet without imposing an excessive load on the expanding device. Even if the device is used continuously over a long period of time, the device fails. Can be expected to prevent. In addition, the measuring method of 100% stress in the MD direction is as shown in a test example described later.

The semiconductor processing sheet according to the present embodiment preferably has adhesiveness on at least one surface. Thereby, it becomes possible to stick and fix a semiconductor chip etc. on the said surface. In the present specification, the surface of the semiconductor processing sheet that has adhesiveness and is attached with a semiconductor chip or the like may be referred to as an “adhesive surface”. The adhesive strength of the semiconductor processing sheet according to the present embodiment is preferably 300 mN / 25 mm or more, particularly preferably 800 mN / 25 mm or more, and more preferably 1000 mN / 25 mm or more. The adhesive strength is preferably 30000 mN / 25 mm or less, particularly preferably 15000 mN / 25 mm or less, and more preferably 10000 mN / 25 mm or less. When the adhesive force is 300 mN / 25 mm or more, a semiconductor chip or the like can be satisfactorily adhered and fixed to the adhesive surface. In addition, when the adhesive force is 30000 mN / 25 mm or less, the semiconductor processing sheet according to the present embodiment is replaced with another semiconductor sheet or the like, and the semiconductor processing sheet according to the present embodiment is changed to a semiconductor. Transfer of the semiconductor chip or the like to a holding member capable of attracting and holding the chip or the like, pickup of the semiconductor chip from the semiconductor processing sheet according to the present embodiment, and the like can be performed satisfactorily. In the present specification, the adhesive strength is an adhesive strength (mN / 25 mm) measured by a 180 ° peeling method according to JIS Z0237: 2009 using a silicon mirror wafer as an adherend. In addition, when the semiconductor processing sheet according to the present embodiment is composed only of a base material, the adhesive strength is measured on one surface of the base material, and the semiconductor processing sheet according to the present embodiment is based on the base material. When it consists of a material and the adhesive layer mentioned later, adhesive force shall be measured about the surface on the opposite side to the base material in the said adhesive layer.

The semiconductor processing sheet according to the present embodiment preferably has heat resistance. When a wafer level package is manufactured using the semiconductor processing sheet according to the present embodiment, the semiconductor chip may be sealed with a sealing member on the semiconductor processing sheet according to the present embodiment. Generally, a thermosetting material is used as the sealing member, and the material is heated at the time of sealing. When the semiconductor processing sheet has heat resistance, it is possible to suppress deformation of the semiconductor processing sheet due to the heating.

The thickness of the semiconductor processing sheet according to this embodiment is preferably 30 μm or more, and particularly preferably 50 μm or more. Further, the thickness is preferably 300 μm or less, and particularly preferably 250 μm or less.

2. Base Material The base material of the semiconductor processing sheet according to the present embodiment is not particularly limited as long as the semiconductor processing sheet can achieve the above-described physical properties. Usually, a resin-based material is a main material. It is comprised from the film. In particular, from the viewpoint of easily achieving the above-described physical properties, it is preferable to use a thermoplastic elastomer or a rubber-based material as the base material. Among these, from the viewpoint of easily achieving the above-described physical properties, It is particularly preferred to use a thermoplastic elastomer. In addition, from the viewpoint of easily achieving the above-described physical properties, it is preferable to use a resin having a relatively low glass transition temperature (Tg) as a constituent material of the base material. In particular, the glass transition temperature ( Tg) is preferably 90 ° C. or lower, particularly preferably 80 ° C. or lower, and more preferably 70 ° C. or lower.

Examples of thermoplastic elastomers include urethane elastomers, olefin elastomers, vinyl chloride elastomers, polyester elastomers, styrene elastomers, acrylic elastomers, and amide elastomers. Among these, it is preferable to use a urethane elastomer from the viewpoint that the above-described physical properties are more easily achieved.

A urethane-based elastomer is generally obtained by reacting a long-chain polyol, a chain extender and a diisocyanate, and a soft segment having a structural unit derived from a long-chain polyol, and a reaction between the chain extender and the diisocyanate. From a hard segment having a polyurethane structure.

When urethane-based elastomers are classified according to the type of long-chain polyol used as the soft segment component, they can be classified into polyester-based polyurethane elastomers, polyether-based polyurethane elastomers, polycarbonate-based polyurethane elastomers, and the like. In the semiconductor processing sheet according to the present embodiment, among these, it is preferable to use a polyether-based polyurethane elastomer from the viewpoint of easily achieving the above-described physical properties.

Examples of the long-chain polyol include polyester polyols such as lactone polyester polyols and adipate polyester polyols; polyether polyols such as polypropylene (ethylene) polyol and polytetramethylene ether glycol; polycarbonate polyols and the like. Among these, it is preferable to use an adipate polyester polyol from the viewpoint of easily achieving the above-described physical properties.

Examples of the diisocyanate include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, and the like. Among these, it is preferable to use hexamethylene diisocyanate from the viewpoint of easily achieving the physical properties described above.

Examples of the chain extender include low molecular weight polyhydric alcohols such as 1,4-butanediol and 1,6-hexanediol, and aromatic diamines. Of these, 1,6-hexanediol is preferably used from the viewpoint of easily achieving the above-described physical properties.

Examples of olefin elastomers include ethylene / α-olefin copolymers, propylene / α-olefin copolymers, butene / α-olefin copolymers, ethylene / propylene / α-olefin copolymers, ethylene / butene / α- At least selected from the group consisting of olefin copolymers, propylene / butene-α olefin copolymers, ethylene / propylene / butene / α / olefin copolymers, styrene / isoprene copolymers and styrene / ethylene / butylene copolymers. The thing containing 1 type of resin is mentioned.

The density of the olefin-based elastomer is not particularly limited, but is 0.860 g / cm ³ or more from the viewpoint of more stably obtaining a substrate excellent in unevenness followability when a semiconductor wafer is attached to a semiconductor processing sheet. it is preferably less than .905g / cm ^3, more preferably less than 0.862 g / cm ³ or more 0.900 g / cm ^3, less than 0.864 g / cm ³ or more 0.895 g / cm ³ Is particularly preferred.

The olefin-based elastomer has a mass ratio (also referred to as “olefin content” in the present specification) of a monomer composed of an olefin-based compound of all monomers used for forming the elastomer of 50 to 100. It is preferable that it is mass%. When the olefin content is excessively low, properties as an elastomer containing structural units derived from olefins are hardly exhibited, and flexibility and rubber elasticity are hardly exhibited. From the viewpoint of stably obtaining such an effect, the olefin content is preferably 50% by mass or more, and more preferably 60% by mass or more.

Examples of the styrene elastomer include styrene-conjugated diene copolymer and styrene-olefin copolymer. Specific examples of the styrene-conjugated diene copolymer include styrene-butadiene copolymer, styrene-butadiene-styrene copolymer (SBS), styrene-butadiene-butylene-styrene copolymer, styrene-isoprene copolymer, Unhydrogenated styrene-conjugated diene copolymers such as styrene-isoprene-styrene copolymer (SIS) and styrene-ethylene-isoprene-styrene copolymer; styrene-ethylene / propylene-styrene copolymer (SEPS, styrene- Hydrogenated styrene-conjugated diene copolymers such as isoprene-styrene copolymer water additives) and styrene-ethylene-butylene-styrene copolymers (SEBS, hydrogenated styrene-butadiene copolymers). be able to. Industrially, Tufprene (Asahi Kasei), Clayton (Clayton Polymer Japan), Sumitomo TPE-SB (Sumitomo Chemical), Epofriend (Daicel Chemical Industries), Lavalon (Mitsubishi Chemical) ), Septon (manufactured by Kuraray), Tuftec (manufactured by Asahi Kasei), and the like. The styrene elastomer may be a hydrogenated product or an unhydrogenated product.

Examples of rubber materials include natural rubber, synthetic isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile-butadiene copolymer rubber (NBR), butyl rubber ( IIR), halogenated butyl rubber, acrylic rubber, urethane rubber, polysulfide rubber and the like, and these can be used alone or in combination of two or more.

As the base material, a film in which a plurality of films made of the above materials are laminated can be used. Moreover, what laminated | stacked the film which consists of the above materials, and another film can also be used.

In the case of laminating a plurality of layers of films, a film having a high contribution rate in achieving the above-described physical properties is arranged in the center with a relatively thick thickness, and the film is formed with a relatively thin thickness with a low contribution rate. It can be configured to be sandwiched between different films. In addition, the use of a resin having a relatively low glass transition temperature (Tg) is preferable for achieving the above-described physical properties. However, since such a resin has high adhesiveness, such a resin is used on the surface of a semiconductor processing sheet. When it is provided, it may be difficult to handle the semiconductor processing sheet during manufacture or use. Therefore, a resin film having a relatively low glass transition temperature (Tg) is sandwiched between resin films having a relatively high glass transition temperature (Tg), or a glass transition temperature relative to a resin film having a relatively low glass transition temperature (Tg). By laminating a resin film having a relatively high (Tg), it is possible to achieve both the achievement of the above-described physical properties and the handleability.

When the semiconductor processing sheet according to the present embodiment is composed only of a base material, the base material preferably has adhesiveness. When the said adhesiveness is what is exhibited by a normal state, it is preferable to use what has self-adhesiveness as a base material.

In addition, when the semiconductor processing sheet according to the present embodiment is composed of only a base material and the base material is formed by laminating a plurality of films, among the plurality of laminated films, the sheet is positioned in the outermost layer. Only the film to perform or only one of them may have adhesiveness. For example, by laminating a resin film with a relatively high glass transition temperature (Tg) on one surface of a resin film with a relatively low glass transition temperature (Tg), it exhibits adhesiveness only on that one surface. Can be made. The outermost layer of the semiconductor processing sheet in this specification does not include a release sheet or the like that is removed during use.

In the base material in the present embodiment, various additives such as pigments, dyes, flame retardants, plasticizers, antistatic agents, lubricants, fillers, and the like may be included in the film mainly composed of the resin material. Good. Examples of the pigment include titanium dioxide and carbon black. Examples of the filler include organic materials such as melamine resin, inorganic materials such as fumed silica, and metal materials such as nickel particles. The content of such an additive is not particularly limited, but it is preferable to keep the content within a range in which the base material can exhibit a desired function.

When the semiconductor processing sheet has a pressure-sensitive adhesive layer described later, the base material is formed on one surface or both surfaces as desired by an oxidation method or an unevenness method for the purpose of improving adhesion with the pressure-sensitive adhesive layer laminated on the surface. The surface treatment by the above, or the primer treatment for forming the primer layer can be performed. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet), flame treatment, hot air treatment, ozone, ultraviolet irradiation treatment, and the like. Examples include a thermal spraying method.

Further, when the pressure-sensitive adhesive layer contains an energy ray-curable pressure-sensitive adhesive, it is preferable that the substrate has transparency to energy rays. In particular, when ultraviolet rays are used as energy rays, the substrate preferably has transparency to ultraviolet rays, and when electron beams are used as energy rays, the substrate may have electron beam transparency. preferable.

In the semiconductor processing sheet according to the present embodiment, the substrate production method is not particularly limited. For example, a cast molding method (melt casting method), a melt extrusion method such as a T-die method or an inflation method, a calendar method, or the like. Any method may be used. Especially, it is preferable to manufacture a base material by the cast molding method from a viewpoint that it is easy to suppress variation in thickness. In this case, after casting a liquid compound (resin before curing, resin solution, etc.) into a thin film on the process sheet, the coating is cured to form a film. It is preferable that can be manufactured.

The thickness of the substrate is not limited as long as the semiconductor processing sheet can function properly in a desired process. The thickness of the substrate is preferably 20 μm or more, and particularly preferably 40 μm or more. Further, the thickness is preferably 250 μm or less, and particularly preferably 200 μm or less.

Further, the standard deviation of the thickness of the base material when the thickness is measured at intervals of 2 cm is preferably 2 μm or less, particularly preferably 1.5 μm or less, and further preferably 1 μm or less. . When the standard deviation is 2 μm or less, the semiconductor processing sheet has a highly accurate thickness, and the semiconductor processing sheet can be uniformly stretched.

3. Adhesive Layer The semiconductor processing sheet according to the present embodiment preferably further includes an adhesive layer laminated on at least one surface of the substrate. Thereby, the semiconductor processing sheet easily exhibits desired adhesiveness on the surface on the pressure-sensitive adhesive layer side, and a semiconductor chip or the like can be satisfactorily adhered to the surface.

The pressure-sensitive adhesive layer is not particularly limited as long as the physical properties described above can be achieved in the semiconductor processing sheet. The pressure-sensitive adhesive layer may be composed of a non-energy ray curable pressure sensitive adhesive or an energy ray curable pressure sensitive adhesive. As the non-energy ray curable pressure-sensitive adhesive, those having desired adhesive strength and removability are preferable. For example, acrylic pressure-sensitive adhesive, rubber-based pressure-sensitive adhesive, silicone-based pressure-sensitive adhesive, urethane-based pressure-sensitive adhesive, and polyester-based pressure-sensitive adhesive Polyvinyl ether-based pressure-sensitive adhesives can be used. Among these, an acrylic pressure-sensitive adhesive that can effectively suppress dropping of a semiconductor chip or the like when the semiconductor processing sheet is stretched is preferable.

On the other hand, the energy ray curable adhesive is cured by energy ray irradiation and its adhesive strength is reduced. Therefore, when it is desired to separate the semiconductor chip and the semiconductor processing sheet, it can be easily separated by irradiating the energy ray. be able to.

The energy ray-curable pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer may be mainly composed of a polymer having energy ray-curability, or a non-energy ray-curable polymer (polymer not having energy ray-curability). And a mixture of a monomer and / or an oligomer having at least one energy ray curable group. Further, it may be a mixture of a polymer having energy ray curable properties and a non-energy ray curable polymer, a polymer having energy ray curable properties and a monomer having at least one energy ray curable group and / or It may be a mixture with an oligomer or a mixture of these three.

First, the case where the energy ray-curable pressure-sensitive adhesive is composed mainly of a polymer having energy ray-curability will be described below.

The polymer having energy ray curability is a (meth) acrylic acid ester (co) polymer (A) (hereinafter referred to as “energy ray”) in which a functional group having energy ray curability (energy ray curable group) is introduced into the side chain. It may be referred to as “curable polymer (A)”). This energy beam curable polymer (A) reacts an acrylic copolymer (a1) having a functional group-containing monomer unit with an unsaturated group-containing compound (a2) having a functional group bonded to the functional group. It is preferable that it is obtained. In this specification, (meth) acrylic acid ester means both acrylic acid ester and methacrylic acid ester. The same applies to other similar terms.

The acrylic copolymer (a1) preferably contains a structural unit derived from a functional group-containing monomer and a structural unit derived from a (meth) acrylic acid ester monomer or a derivative thereof.

The functional group-containing monomer as a constituent unit of the acrylic copolymer (a1) contains a polymerizable double bond and a functional group such as a hydroxy group, a carboxy group, an amino group, a substituted amino group, and an epoxy group in the molecule. It is preferable that the monomer has

Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl ( Examples thereof include meth) acrylate and 4-hydroxybutyl (meth) acrylate, and these are used alone or in combination of two or more.

Examples of the carboxy group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These may be used alone or in combination of two or more.

Examples of the amino group-containing monomer or substituted amino group-containing monomer include aminoethyl (meth) acrylate and n-butylaminoethyl (meth) acrylate. These may be used alone or in combination of two or more.

Examples of the (meth) acrylic acid ester monomer constituting the acrylic copolymer (a1) include an alkyl (meth) acrylate having an alkyl group having 1 to 20 carbon atoms, and an alicyclic structure in the molecule, for example. The monomer (alicyclic structure-containing monomer) is preferably used.

Examples of the alkyl (meth) acrylate include alkyl (meth) acrylates having an alkyl group having 1 to 18 carbon atoms, such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate and the like are preferably used. These may be used individually by 1 type and may be used in combination of 2 or more type.

Examples of the alicyclic structure-containing monomer include cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, adamantyl (meth) acrylate, isobornyl (meth) acrylate, and dicyclopentenyl (meth) acrylate. , Dicyclopentenyloxyethyl (meth) acrylate and the like are preferably used. These may be used individually by 1 type and may be used in combination of 2 or more type.

The acrylic copolymer (a1) contains the structural unit derived from the functional group-containing monomer, preferably in an amount of 1% by mass or more, particularly preferably 5% by mass or more, and more preferably 10% by mass or more. The acrylic copolymer (a1) preferably contains a constituent unit derived from the functional group-containing monomer in a proportion of 35% by mass or less, particularly preferably 30% by mass or less, and more preferably 25% by mass or less. To do.

Furthermore, the acrylic copolymer (a1) preferably contains 50% by mass or more, particularly preferably 60% by mass or more, and further preferably 70% by mass of a structural unit derived from a (meth) acrylic acid ester monomer or a derivative thereof. It contains in the above ratio. The acrylic copolymer (a1) preferably contains 99% by mass or less, particularly preferably 95% by mass or less, and more preferably 90% by mass of a structural unit derived from a (meth) acrylic acid ester monomer or a derivative thereof. Contains in the following proportions.

The acrylic copolymer (a1) can be obtained by copolymerizing a functional group-containing monomer as described above with a (meth) acrylic acid ester monomer or a derivative thereof in a conventional manner. Dimethylacrylamide, vinyl formate, vinyl acetate, styrene and the like may be copolymerized.

By reacting the acrylic copolymer (a1) having the functional group-containing monomer unit with an unsaturated group-containing compound (a2) having a functional group bonded to the functional group, an energy beam curable polymer (A ) Is obtained.

The functional group of the unsaturated group-containing compound (a2) can be appropriately selected according to the type of functional group of the functional group-containing monomer unit of the acrylic copolymer (a1). For example, when the functional group of the acrylic copolymer (a1) is a hydroxy group, an amino group or a substituted amino group, the functional group of the unsaturated group-containing compound (a2) is preferably an isocyanate group or an epoxy group. When the functional group that the system copolymer (a1) has is an epoxy group, the functional group that the unsaturated group-containing compound (a2) has is preferably an amino group, a carboxy group, or an aziridinyl group.

The unsaturated group-containing compound (a2) contains at least one, preferably 1-6, more preferably 1-4, energy-polymerizable carbon-carbon double bonds in one molecule. ing. Specific examples of such unsaturated group-containing compound (a2) include, for example, 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α, α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1- ( Bisacryloyloxymethyl) ethyl isocyanate; acryloyl monoisocyanate compound obtained by reaction of diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth) acrylate; diisocyanate compound or polyisocyanate compound, polyol compound, and hydroxyethyl (meth) Acryloyl monoisocyanate compound obtained by reaction with acrylate; glycidyl (meth) acrylate; (meth) acrylic acid, 2- (1 -Aziridinyl) ethyl (meth) acrylate, 2-vinyl-2-oxazoline, 2-isopropenyl-2-oxazoline and the like.

The unsaturated group-containing compound (a2) is preferably at least 50 mol%, particularly preferably at least 60 mol%, more preferably 70 mol, based on the number of moles of the functional group-containing monomer of the acrylic copolymer (a1). % Is used at a rate of at least%. In addition, the unsaturated group-containing compound (a2) is preferably 95 mol% or less, particularly preferably 93 mol% or less, more preferably, relative to the number of moles of the functional group-containing monomer of the acrylic copolymer (a1). It is used at a ratio of 90 mol% or less.

In the reaction between the acrylic copolymer (a1) and the unsaturated group-containing compound (a2), the functional group of the acrylic copolymer (a1) and the functional group of the unsaturated group-containing compound (a2) Depending on the combination, the reaction temperature, pressure, solvent, time, presence / absence of catalyst, and type of catalyst can be appropriately selected. As a result, the functional group present in the acrylic copolymer (a1) reacts with the functional group in the unsaturated group-containing compound (a2), so that the unsaturated group is contained in the acrylic copolymer (a1). It introduce | transduces into a side chain and an energy-beam curable polymer (A) is obtained.

The weight average molecular weight (Mw) of the energy ray curable polymer (A) thus obtained is preferably 10,000 or more, particularly preferably 150,000 or more, and more preferably 200,000 or more. Is preferred. The weight average molecular weight (Mw) is preferably 1.5 million or less, and particularly preferably 1 million or less. In addition, the weight average molecular weight (Mw) in this specification is the value of standard polystyrene conversion measured by the gel permeation chromatography method (GPC method).

Even when the energy ray curable adhesive is mainly composed of an energy ray curable polymer such as an energy ray curable polymer (A), the energy ray curable adhesive is an energy ray curable monomer. And / or the oligomer (B) may further be contained.

As the energy ray-curable monomer and / or oligomer (B), for example, an ester of a polyhydric alcohol and (meth) acrylic acid or the like can be used.

Examples of the energy ray-curable monomer and / or oligomer (B) include monofunctional acrylic acid esters such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, penta Erythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol Polyfunctional acrylic esters such as di (meth) acrylate and dimethyloltricyclodecane di (meth) acrylate, polyester oligo (meth) acrylate, polyurethane oligo (meta Acrylate, and the like.

When the energy ray curable monomer (B) is blended with the energy ray curable polymer (A), the energy ray curable monomer and / or oligomer (B) in the energy ray curable adhesive is used. ) Content is preferably more than 0 parts by mass, particularly preferably 60 parts by mass or more, with respect to 100 parts by mass of the energy ray-curable polymer (A). In addition, the content is preferably 250 parts by mass or less, particularly preferably 200 parts by mass or less, with respect to 100 parts by mass of the energy beam curable polymer (A).

Here, when using ultraviolet rays as energy rays for curing the energy ray-curable pressure-sensitive adhesive, it is preferable to add a photopolymerization initiator (C), and by using this photopolymerization initiator (C), The polymerization curing time and the amount of light irradiation can be reduced.

Specific examples of the photopolymerization initiator (C) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, benzoin dimethyl ketal, 2,4-diethylthioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, β-chloranthraquinone, (2,4 6-trimethylbenzyldiphenyl) phosphine oxide, 2-benzothiazole-N, N-diethyldithiocarbamate, oligo {2-hydroxy-2-me Le-1- [4- (1-propenyl) phenyl] propanone}, and 2,2-dimethoxy-1,2-and the like. These may be used alone or in combination of two or more.

The photopolymerization initiator (C) is energy beam curable copolymer (A) (when energy beam curable monomer and / or oligomer (B) is blended, energy beam curable copolymer (A). The total amount of the energy ray-curable monomer and / or oligomer (B) is 100 parts by mass) and is preferably used in an amount of 0.1 parts by mass or more, particularly 0.5 parts by mass or more with respect to 100 parts by mass. The photopolymerization initiator (C) is energy beam curable copolymer (A) (when energy beam curable monomer and / or oligomer (B) is blended, energy beam curable copolymer ( The total amount of A) and energy ray-curable monomer and / or oligomer (B) is 100 parts by mass) and is preferably used in an amount of 10 parts by mass or less, particularly 6 parts by mass or less.

In the energy ray-curable pressure-sensitive adhesive, other components may be appropriately blended in addition to the above components. Examples of other components include a non-energy ray curable polymer component or oligomer component (D), and a crosslinking agent (E).

Examples of the non-energy ray curable polymer component or oligomer component (D) include polyacrylates, polyesters, polyurethanes, polycarbonates, polyolefins, etc., and polymers or oligomers having a weight average molecular weight (Mw) of 3000 to 2.5 million. Is preferred. By mix | blending the said component (D) with energy-beam curable adhesive, the adhesiveness and peelability before hardening, the intensity | strength after hardening, the adhesiveness with another layer, storage stability, etc. can be improved. The compounding quantity of the said component (D) is not specifically limited, It determines suitably in the range of more than 0 mass part and 50 mass parts or less with respect to 100 mass parts of energy-beam curable copolymers (A).

As the crosslinking agent (E), a polyfunctional compound having reactivity with the functional group of the energy beam curable copolymer (A) or the like can be used. Examples of such polyfunctional compounds include isocyanate compounds, epoxy compounds, amine compounds, melamine compounds, aziridine compounds, hydrazine compounds, aldehyde compounds, oxazoline compounds, metal alkoxide compounds, metal chelate compounds, metal salts, ammonium salts, A reactive phenol resin etc. can be mentioned.

The amount of the crosslinking agent (E) is preferably 0.01 parts by mass or more, particularly 0.03 parts by mass or more, with respect to 100 parts by mass of the energy ray curable copolymer (A). More preferably, it is 0.04 parts by mass or more. The amount of the crosslinking agent (E) is preferably 8 parts by mass or less, particularly preferably 5 parts by mass or less, with respect to 100 parts by mass of the energy ray curable copolymer (A). Furthermore, it is preferable that it is 3.5 mass parts or less.

Next, the case where the energy beam curable pressure-sensitive adhesive is mainly composed of a mixture of a non-energy beam curable polymer component and a monomer and / or oligomer having at least one energy beam curable group will be described below. .

As the non-energy ray curable polymer component, for example, the same components as the acrylic copolymer (a1) described above can be used.

As the monomer and / or oligomer having at least one energy ray curable group, the same one as the above-mentioned component (B) can be selected. The blending ratio of the non-energy ray curable polymer component and the monomer and / or oligomer having at least one energy ray curable group is at least one or more with respect to 100 parts by mass of the non-energy ray curable polymer component. The amount of the monomer and / or oligomer having an energy ray-curable group is preferably 1 part by mass or more, and particularly preferably 60 parts by mass or more. The blending ratio is preferably not more than 200 parts by mass of monomers and / or oligomers having at least one energy ray-curable group with respect to 100 parts by mass of the non-energy ray-curable polymer component. It is preferably less than or equal to parts by mass.

Also in this case, the photopolymerization initiator (C) and the crosslinking agent (E) can be appropriately blended as described above.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, and is preferably, for example, 3 μm or more, and particularly preferably 5 μm or more. The thickness is preferably 50 μm or less, and particularly preferably 40 μm or less.

4). Release sheet The semiconductor processing sheet according to the present embodiment may be laminated with a release sheet for the purpose of protecting the adhesive surface until the adhesive surface is attached to an adherend such as a semiconductor chip. . The configuration of the release sheet is arbitrary, and examples include a release film of a plastic film with a release agent. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. As the release agent, silicone-based, fluorine-based, long-chain alkyl-based, and the like can be used, and among these, a silicone-based material that is inexpensive and provides stable performance is preferable. The thickness of the release sheet is not particularly limited, but is usually about 20 to 250 μm.

5). Manufacturing Method of Semiconductor Processing Sheet The semiconductor processing sheet according to this embodiment can be manufactured in the same manner as a conventional semiconductor processing sheet. In particular, as a method for producing a semiconductor processing sheet comprising a substrate and a pressure-sensitive adhesive layer, a detailed method is particularly suitable if a pressure-sensitive adhesive layer formed from the above-mentioned pressure-sensitive adhesive composition can be laminated on one surface of the substrate. It is not limited. For example, a pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer and, if desired, a coating liquid further containing a solvent or a dispersion medium are prepared, and a die coater, a curtain coater, and a spray are formed on one surface of the substrate. The pressure-sensitive adhesive layer can be formed by applying the coating solution with a coater, slit coater, knife coater or the like to form a coating film and drying the coating film. The properties of the coating liquid are not particularly limited as long as it can be applied, and may contain a component for forming the pressure-sensitive adhesive layer as a solute or a dispersoid.

Moreover, as another example of the manufacturing method of the sheet | seat for semiconductor processing, a coating liquid is apply | coated on the peeling surface of the above-mentioned peeling sheet, a coating film is formed, this is dried, an adhesive layer and a peeling sheet, A laminate of the semiconductor processing sheet and the release sheet may be obtained by forming a laminate made of the above and affixing the surface opposite to the release sheet side of the adhesive layer of the laminate to the substrate. . The release sheet in this laminate may be peeled off as a process material, or the adhesive layer may be protected until being attached to an adherend such as a semiconductor chip or a semiconductor wafer.

When the coating solution contains a cross-linking agent, the non-energy ray-curable acrylic adhesive in the coating film can be changed by changing the drying conditions (temperature, time, etc.) or by separately providing a heat treatment. The crosslinking reaction between the agent (N) or the energy ray-curable pressure-sensitive adhesive (A) and the crosslinking agent may be advanced to form a crosslinked structure at a desired density in the pressure-sensitive adhesive layer. In order to sufficiently proceed with the crosslinking reaction, after the pressure-sensitive adhesive layer is laminated on the base material by the above-described method, the obtained semiconductor processing sheet is placed in an environment of, for example, 23 ° C. and a relative humidity of 50% for several days. Curing such as leaving still may be performed.

6). Method for Using Semiconductor Processing Sheet The semiconductor processing sheet according to the present embodiment can be used, for example, to increase the interval between a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet.

In particular, it is preferably used to increase the interval between adjacent semiconductor chips in a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet by 200 μm or more. The upper limit of the interval is not particularly limited, but may be 6000 μm, for example.

Further, the semiconductor processing sheet according to the present embodiment can also be used when the interval between a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet is expanded by at least biaxial stretching. In this case, for example, the semiconductor processing sheet is stretched by applying tension in four directions of the + X axis direction, the −X axis direction, the + Y axis direction, and the −Y axis direction on the X axis and the Y axis orthogonal to each other. More specifically, the film is stretched in the MD direction and the CD direction, respectively.

The biaxial stretching as described above can be performed using, for example, a separation device that applies tension in the X-axis direction and the Y-axis direction. Here, the X axis and the Y axis are orthogonal to each other, and one of the directions parallel to the X axis is the + X axis direction, the opposite direction to the + X axis direction is the −X axis direction, and the direction parallel to the Y axis. One of them is defined as a + Y axis direction, and a direction opposite to the + Y axis direction is defined as a −Y axis direction.

The spacing device applies tension to the semiconductor processing sheet in four directions of + X axis direction, -X axis direction, + Y axis direction, and -Y axis direction, and a plurality of holding means in each of these four directions And a plurality of tension applying means corresponding to them. The number of holding means and tension applying means in each direction may be, for example, about 3 or more and 10 or less, depending on the size of the semiconductor processing sheet.

Here, for example, in a group including a plurality of holding means and a plurality of tension applying means provided for applying tension in the + X-axis direction, each holding means includes a holding member that holds the semiconductor processing sheet. It is preferable that each tension applying means applies a tension to the semiconductor processing sheet by moving the holding member corresponding to the tension applying means in the + X-axis direction. And it is preferable that the several tension | tensile_strength provision means is provided so that a holding | maintenance means may be moved to + X-axis direction each independently. The same configuration is also applied to three groups including a plurality of holding means and a plurality of tension applying means provided for applying tension in the −X axis direction, the + Y axis direction, and the −Y axis direction, respectively. It is preferable to have. Thereby, the said separation apparatus can give tension | tensile_strength of a magnitude | size different with respect to the sheet | seat for semiconductor processing for every area | region of the direction orthogonal to each direction.

In general, when a semiconductor processing sheet is held from four directions of + X axis direction, -X axis direction, + Y axis direction, and -Y axis direction using four holding members and stretched in the four directions, semiconductor processing In addition to these four directions, the composite sheet includes these composite directions (for example, the composite direction of the + X axis direction and the + Y axis direction, the composite direction of the + Y axis direction and the −X axis direction, the −X axis direction and the −Y axis) The tension is also applied to the composite direction with the direction and the composite direction of the −Y axis direction and the + X axis direction). As a result, there may be a difference in the distance between the semiconductor chips inside the semiconductor processing sheet and the distance between the semiconductor chips outside.

However, in the above-described separation device, the plurality of tension applying means independently apply tension to the semiconductor processing sheet in each of the + X axis direction, the −X axis direction, the + Y axis direction, and the −Y axis direction. Therefore, the semiconductor processing sheet can be stretched so that the difference between the inner side and the outer side of the semiconductor processing sheet as described above is eliminated. As a result, the interval between the semiconductor chips can be adjusted accurately.

It is preferable that the spacing device further includes a measuring unit that measures the mutual spacing of the semiconductor chips. Here, it is preferable that the tension applying means is provided so that a plurality of holding members can be individually moved based on the measurement result of the measuring means. Thereby, based on the measurement result of the interval between the semiconductor chips by the measuring means, the interval can be further adjusted, and as a result, the interval between the semiconductor chips can be adjusted more accurately.

In the spacing device, the holding means may be a chuck means such as a mechanical chuck or a chuck cylinder, a pressure reducing means such as a vacuum pump or a vacuum ejector, or a semiconductor processing sheet by an adhesive, magnetic force, or the like. The structure which supports may be sufficient. Further, as the holding member in the chuck means, for example, a lower support member that supports the semiconductor processing sheet from below, a drive device supported by the lower support member, and an output shaft of the drive device, the drive device is driven. By doing so, what has the structure provided with the upper support member which can press down the sheet | seat for semiconductor processing from the top can be used. Examples of the drive device include electric devices such as a rotation motor, a linear motion motor, a linear motor, a single-axis robot, and an articulated robot, and actuators such as an air cylinder, a hydraulic cylinder, a rodless cylinder, and a rotary cylinder. .

Further, in the above separating apparatus, the tension applying means may include a driving device, and the holding member may be moved by the driving device. As the driving device, those described above can be used. For example, the tension applying means includes a linear motion motor as a drive device, and an output shaft interposed between the linear motion motor and the holding member, and the driven linear motion motor moves the holding member via the output shaft. It may be a configuration.

When the interval between the semiconductor chips is increased using the semiconductor processing sheet according to the present embodiment, the interval may be increased from a state where the semiconductor chips are in contact with each other, or a state where the interval between the semiconductor chips is hardly increased, or The distance between the semiconductor chips may be further increased from the state in which the distance between the semiconductor chips is already increased to a predetermined distance.

For example, after obtaining a plurality of semiconductor chips by dividing a semiconductor wafer on a dicing sheet, the semiconductor chips are in contact with each other or the gap between the semiconductor chips is not widened. A plurality of semiconductor chips can be transferred from the dicing sheet to the semiconductor processing sheet according to the present embodiment, and then the interval between the semiconductor chips can be increased. Alternatively, after the semiconductor wafer is divided on the semiconductor processing sheet according to the present embodiment to obtain a plurality of semiconductor chips, the interval between the semiconductor chips can be increased.

In the case where the distance between the semiconductor chips is already expanded to a predetermined distance, the semiconductor chip can be further expanded by using another semiconductor processing sheet, preferably the semiconductor processing sheet according to the present embodiment. The semiconductor chip is transferred from the sheet to the semiconductor processing sheet according to the present embodiment, and then the semiconductor processing sheet according to the present embodiment is stretched to extend the semiconductor chip. Can be further widened. Such transfer of the semiconductor chip and stretching of the semiconductor processing sheet may be repeated a plurality of times until the distance between the semiconductor chips reaches a desired distance.

Furthermore, the semiconductor processing sheet according to the present embodiment is preferably used for applications that require a relatively large gap between the semiconductor chips. Examples of such applications include fan-out type semiconductor wafer levels. A method for producing a package (FO-WLP) is preferred. Examples of such a method for producing FO-WLP include a first aspect and a second aspect described below.

(1) First Aspect Hereinafter, a first aspect of a method for manufacturing FO-WLP using a semiconductor processing sheet according to the present embodiment will be described. In addition, in this 1st aspect, the sheet | seat for semiconductor processing which concerns on this embodiment is used as the 2nd adhesive sheet 20 mentioned later.

FIG. 1A shows a semiconductor wafer W adhered to the first adhesive sheet 10. The semiconductor wafer W has a circuit surface W1, and a circuit W2 is formed on the circuit surface W1. The first adhesive sheet 10 is attached to the back surface W3 of the semiconductor wafer W opposite to the circuit surface W1. The first pressure-sensitive adhesive sheet 10 has a first base film 11 and a first pressure-sensitive adhesive layer 12. The first pressure-sensitive adhesive layer 12 is laminated on the first base film 11.

[Dicing process]
FIG. 1B shows a plurality of semiconductor chips CP held on the first pressure-sensitive adhesive sheet 10.

The semiconductor wafer W held on the first adhesive sheet 10 is divided into pieces by dicing, and a plurality of semiconductor chips CP are formed. A cutting means such as a dicing saw is used for dicing. The cutting depth at the time of dicing is set to a depth that takes into account the total thickness of the semiconductor wafer W, the first pressure-sensitive adhesive layer 12, and the wear of the dicing saw. The first pressure-sensitive adhesive layer 12 is also cut into the same size as the semiconductor chip CP by dicing. Furthermore, a cut may be formed in the first base film 11 by dicing.

Note that dicing may be performed by irradiating the semiconductor wafer W with laser light instead of using the above-described cutting means such as a dicing saw. For example, the semiconductor wafer W may be completely divided by laser light irradiation and separated into a plurality of semiconductor chips CP. Alternatively, after the modified layer is formed inside the semiconductor wafer W by laser light irradiation, the first adhesive sheet 10 is stretched in the first expanding step described later, so that the semiconductor wafer W is positioned at the modified layer position. It may be broken and separated into semiconductor chips CP (stealth dicing). In the case of stealth dicing, for example, laser light irradiation is performed such that infrared laser light is focused on a focal point set inside the semiconductor wafer W. In these methods, laser light irradiation may be performed from any side of the semiconductor wafer W.

[First expanding process]
FIG. 1C shows a diagram for explaining a process of extending the first pressure-sensitive adhesive sheet 10 that holds a plurality of semiconductor chips CP (hereinafter also referred to as “first expanding process”).

After dicing into a plurality of semiconductor chips CP by dicing, the first adhesive sheet 10 is stretched to widen the interval between the plurality of semiconductor chips CP. Further, when stealth dicing is performed, the first adhesive sheet 10 is stretched to break the semiconductor wafer W at the position of the modified layer and separate into a plurality of semiconductor chips CP. Increase the spacing between CPs. The method for extending the first pressure-sensitive adhesive sheet 10 in the first expanding step is not particularly limited. Examples of the method of stretching the first pressure-sensitive adhesive sheet 10 include a method of stretching the first pressure-sensitive adhesive sheet 10 by pressing an annular or circular expander, and an outer peripheral portion of the second pressure-sensitive adhesive sheet using a gripping member or the like. For example, a method of grabbing and stretching.

The first pressure-sensitive adhesive sheet 10 preferably has a tensile elastic modulus suitable for the dicing process described above and also suitable for the first expanding process. From this viewpoint, the first pressure-sensitive adhesive sheet 10 preferably has a higher tensile elastic modulus than the second pressure-sensitive adhesive sheet 20 described later. Thereby, the 1st adhesive sheet 10 can exhibit predetermined expandability, without impairing the performance at the time of dicing, and the 2nd adhesive sheet 20 can exhibit the further excellent expandability. .

Note that, as shown in FIG. 1C, the distance between the semiconductor chips CP is D1. The distance D1 is preferably 15 μm or more and 110 μm or less, for example.

[Transfer process]
FIG. 2A is a diagram for explaining a step of transferring a plurality of semiconductor chips CP to the second pressure-sensitive adhesive sheet 20 (hereinafter sometimes referred to as “transfer step”) after the first expanding step. Has been. After extending the first adhesive sheet 10 to increase the distance D1 between the plurality of semiconductor chips CP, the second adhesive sheet 20 is adhered to the circuit surface W1 of the semiconductor chip CP. Here, the semiconductor processing sheet according to the present embodiment is used as the second pressure-sensitive adhesive sheet 20.

The second pressure-sensitive adhesive sheet 20 has a second base film 21 and a second pressure-sensitive adhesive layer 22. It is preferable that the 2nd adhesive sheet 20 is stuck so that the circuit surface W1 may be covered with the 2nd adhesive layer 22. FIG.

It is preferable that the adhesive force of the second adhesive layer 22 is larger than the adhesive force of the first adhesive layer 12. If the adhesive force of the second pressure-sensitive adhesive layer 22 is greater, the first pressure-sensitive adhesive sheet 10 can be easily peeled after the plurality of semiconductor chips CP are transferred to the second pressure-sensitive adhesive sheet 20.

The second adhesive sheet 20 may be adhered to the second ring frame together with the plurality of semiconductor chips CP. In this case, the second ring frame is placed on the second pressure-sensitive adhesive layer 22 of the second pressure-sensitive adhesive sheet 20, and this is lightly pressed and fixed. Thereafter, the second pressure-sensitive adhesive layer 22 exposed inside the ring shape of the second ring frame is pressed against the circuit surface W1 of the semiconductor chip CP to fix the plurality of semiconductor chips CP to the second pressure-sensitive adhesive sheet 20. To do.

When the first pressure-sensitive adhesive sheet 10 is peeled after the second pressure-sensitive adhesive sheet 20 is adhered, the back surfaces W3 of the plurality of semiconductor chips CP are exposed. Even after the first pressure-sensitive adhesive sheet 10 is peeled, it is preferable that the distance D1 between the plurality of semiconductor chips CP expanded in the first expanding step is maintained.

[Second expanding process]
FIG. 2B shows a diagram for explaining a process of extending the second pressure-sensitive adhesive sheet 20 that holds a plurality of semiconductor chips CP (hereinafter also referred to as “second expanding process”).

In the second expanding step, the interval between the plurality of semiconductor chips CP is further expanded. The method of extending the second adhesive sheet 20 in the second expanding step is not particularly limited. Examples of the method for stretching the second pressure-sensitive adhesive sheet 20 include a method of stretching the second pressure-sensitive adhesive sheet 20 by pressing an annular or circular expander, and an outer peripheral portion of the second pressure-sensitive adhesive sheet using a gripping member or the like. For example, a method of grabbing and stretching. As the latter method, for example, a biaxial stretching method using the above-described separation device or the like can be mentioned. Among these, the method of biaxial stretching is preferable from the viewpoint that the interval between the semiconductor chips CP can be greatly increased.

Note that, as shown in FIG. 2B, the interval between the semiconductor chips CP after the second expanding step is D2. The distance D2 is larger than the distance D1. For example, the distance D2 is preferably 200 μm or more and 6000 μm or less.

[Sealing process]
FIG. 2C shows a diagram illustrating a process of sealing a plurality of semiconductor chips CP using the sealing member 60 (hereinafter also referred to as “sealing process”).

The sealing process is performed after the second expanding process. The sealing body 3 is formed by covering the plurality of semiconductor chips CP with the sealing member 60 while leaving the circuit surface W1. The sealing member 60 is also filled between the plurality of semiconductor chips CP. Here, since the circuit surface W1 and the circuit W2 are covered with the second adhesive sheet 20, it is possible to prevent the circuit surface W1 from being covered with the sealing member 60.

By the sealing step, the sealing body 3 in which a plurality of semiconductor chips CP separated by a predetermined distance are embedded in the sealing member 60 is obtained. In the sealing step, the plurality of semiconductor chips CP are preferably covered with the sealing member 60 while the distance D2 is maintained.

After the sealing step, when the second pressure-sensitive adhesive sheet 20 is peeled off, the surface 3A that has been in contact with the circuit surface W1 of the semiconductor chip CP and the second pressure-sensitive adhesive sheet 20 of the sealing body 3 is exposed.

[Rewiring layer forming step and connecting step with external terminal electrode]
FIG. 3A shows a cross-sectional view of the sealing body 3 after the second pressure-sensitive adhesive sheet 20 is peeled off. A rewiring layer forming step for forming a rewiring layer and a step for connecting an external terminal electrode to the formed rewiring layer are sequentially performed on the sealing body 3. In FIG. 3A, the internal terminal electrode W4 is shown as the circuit W2 shown in FIG. 2C in more detail.

The rewiring layer 5 connected to the internal terminal electrode W4 and the external terminal connected to the rewiring layer 5 as shown in FIG. 3B by the rewiring layer forming step and the connecting step with the external terminal electrode. An electrode 6 is formed. Specifically, it is formed as follows. First, the first insulating layer 4A is formed on the circuit surface W1 of the semiconductor chip CP and the surface 3A of the sealing body 3. Subsequently, the rewiring layer 5 is formed so as to be electrically connected to the internal terminal electrode W4. Further, a second insulating layer 4B that covers the rewiring layer 5 is formed. At this time, the rewiring layer 5 is covered with the second insulating layer 4B leaving the external electrode pad 5A. Finally, the external terminal electrode 6 such as a solder ball is placed on the external electrode pad 5A, and the external terminal electrode 6 and the external electrode pad 5A are electrically connected by solder bonding or the like.

[Second dicing process]
FIG. 3C shows a cross-sectional view for explaining a process of separating the sealing body 3 to which the external terminal electrode 6 is connected (hereinafter also referred to as “second dicing process”). Yes. In the second dicing process, the sealing body 3 is separated into individual semiconductor chips CP. The method for dividing the sealing body 3 into individual pieces is not particularly limited. For example, the sealing body 3 can be separated into pieces by adopting a method similar to the method of dicing the semiconductor wafer W described above. The step of dividing the sealing body 3 into pieces may be performed by sticking the sealing body 3 to an adhesive sheet such as a dicing sheet.

The semiconductor package 1 of the semiconductor chip CP unit is manufactured by separating the sealing body 3 into pieces. As described above, the semiconductor package 1 in which the external terminal electrode 6 is connected to the external electrode pad 5A fanned out outside the region of the semiconductor chip CP is manufactured as a fan-out type wafer level package (FO-WLP).

[Modification]
In the FO-WLP manufacturing method according to the first aspect described above, some processes may be changed or some processes may be omitted.

(2) Second Aspect Hereinafter, a second aspect of the FO-WLP manufacturing method using the semiconductor processing sheet according to the present embodiment will be described. Also in this second aspect, the semiconductor processing sheet according to the present embodiment is used as a second adhesive sheet 20 described later.

FIG. 4A shows a semiconductor wafer W attached to a protective sheet 30 as a third adhesive sheet. The semiconductor wafer W has a circuit surface W1 as a first surface, and a circuit W2 is formed on the circuit surface W1. The protective sheet 30 is attached to the circuit surface W1 of the semiconductor wafer W. The protection sheet 30 protects the circuit surface W1 and the circuit W2.

The protective sheet 30 has a third base film 31 and a third pressure-sensitive adhesive layer 32. The third pressure-sensitive adhesive layer 32 is laminated on the third base film 31.

[Groove formation process]
FIG. 4B shows a diagram for explaining a step of forming a groove having a predetermined depth from the circuit surface W1 side of the semiconductor wafer W (hereinafter also referred to as “groove forming step”).

In the groove forming step, the semiconductor wafer W is cut from the protective sheet 30 side using a dicing blade of a dicing apparatus. At that time, the protective sheet 30 is completely cut, and a groove W5 is formed by making a cut with a depth shallower than the thickness of the semiconductor wafer W from the circuit surface W1 of the semiconductor wafer W. The groove W5 is formed so as to partition a plurality of circuits W2 formed on the circuit surface W1 of the semiconductor wafer W. The depth of the groove W5 is not particularly limited as long as it is a little deeper than the thickness of the target semiconductor chip. When the groove W5 is formed, cutting waste from the semiconductor wafer W is generated. In the manufacturing method according to the second aspect, since the groove W5 is formed in a state where the circuit surface W1 is protected by the protective sheet 30, it is possible to prevent contamination and breakage of the circuit surface W1 and the circuit W2 due to cutting waste.

[Grinding process]
FIG. 4C shows a diagram for explaining a process of grinding the back surface W6 as the second surface of the semiconductor wafer W (hereinafter sometimes referred to as “grinding process”) after forming the groove W5. ing.

In the manufacturing method according to the second aspect, the first pressure-sensitive adhesive sheet 10 is adhered to the protective sheet 30 side before grinding. After adhering the first adhesive sheet 10, the semiconductor wafer W is ground from the back surface W 6 side using the grinder 50. By grinding, the thickness of the semiconductor wafer W is reduced and finally divided into a plurality of semiconductor chips CP. Grinding is performed from the back surface W6 side until the bottom of the groove W5 is removed, and the semiconductor wafer W is separated into pieces for each circuit W2. Thereafter, back grinding is further performed as necessary to obtain a semiconductor chip CP having a predetermined thickness. In the manufacturing method according to the second aspect, grinding is performed until the back surface W3 as the third surface is exposed.

FIG. 4D shows a state in which a plurality of divided semiconductor chips CP are held by the protective sheet 30 and the first adhesive sheet 10. In the present specification, as described above, the method of dividing the semiconductor wafer W into the semiconductor chips CP by providing the groove W5 in advance and then grinding the back surface is referred to as “front dicing method”. There is a case.

[Attaching process (second adhesive sheet)]
FIG. 5A shows a diagram for explaining a step of sticking the second pressure-sensitive adhesive sheet 20 to a plurality of semiconductor chips CP (hereinafter also referred to as “sticking step”) after the grinding step. Yes.

The second adhesive sheet 20 is adhered to the back surface W3 of the semiconductor chip CP. The second pressure-sensitive adhesive sheet 20 has a second base film 21 and a second pressure-sensitive adhesive layer 22. Here, the semiconductor processing sheet according to the present embodiment is used as the second pressure-sensitive adhesive sheet 20.

It is preferable that the adhesive force of the second adhesive layer 22 to the semiconductor wafer W is larger than the adhesive force of the third adhesive layer 32 to the semiconductor wafer W. If the adhesive force of the second pressure-sensitive adhesive layer 22 is greater, the first pressure-sensitive adhesive sheet 10 and the protective sheet 30 can be easily peeled off.

The second adhesive sheet 20 may be attached to the ring frame together with the plurality of semiconductor chips CP. In this case, a ring frame is placed on the second pressure-sensitive adhesive layer 22 of the second pressure-sensitive adhesive sheet 20, and this is lightly pressed and fixed. Thereafter, the second adhesive layer 22 exposed inside the ring shape of the ring frame is pressed against the circuit surface W1 of the semiconductor chip CP to fix the plurality of semiconductor chips CP to the second adhesive sheet 20.

[Peeling process (first adhesive sheet)]
FIG. 5B illustrates a step of peeling the first pressure-sensitive adhesive sheet 10 and the protective sheet 30 (hereinafter sometimes referred to as “peeling step”) after attaching the second pressure-sensitive adhesive sheet 20. It is shown.

In the peeling step, when the first pressure-sensitive adhesive sheet 10 is peeled off, the cut protective sheet 30 is accompanied and peeled off. When the protective sheet 30 is peeled off, the circuit surfaces W1 of the plurality of semiconductor chips CP are exposed. Here, as shown in FIG. 5B, the distance between the semiconductor chips CP divided by the previous dicing method is D1. For example, the distance D1 is preferably 15 μm or more and 110 μm or less.

[Expanding process]
FIG. 5C shows a diagram illustrating a process of extending the second pressure-sensitive adhesive sheet 20 that holds a plurality of semiconductor chips CP (hereinafter sometimes referred to as an “expanding process”).

In the expanding process, the interval between the plurality of semiconductor chips CP is further expanded. The method for extending the second pressure-sensitive adhesive sheet 20 in the expanding step is not particularly limited. Examples of the method of stretching the second pressure-sensitive adhesive sheet 20 include a method of stretching the second pressure-sensitive adhesive sheet 20 by pressing an annular or circular expander, and an outer peripheral portion of the second pressure-sensitive adhesive sheet using a gripping member or the like. For example, a method of grabbing and stretching. As the latter method, for example, a biaxial stretching method using the above-described separation device or the like can be mentioned. Among these, the method of biaxial stretching is preferable from the viewpoint that the interval between the semiconductor chips CP can be greatly increased.

In the manufacturing method according to the second aspect, as shown in FIG. 5C, the distance between the semiconductor chips CP after the expanding process is D2. The distance D2 is larger than the distance D1. For example, the distance D2 is preferably 200 μm or more and 6000 μm or less.

[Sealing process]
FIG. 6 is a diagram for explaining a process of sealing a plurality of semiconductor chips CP using the sealing member 60 (hereinafter also referred to as “sealing process”).

FIG. 6 (A) shows a diagram illustrating a process of attaching a surface protection sheet 40 as a fourth pressure-sensitive adhesive sheet to a plurality of semiconductor chips CP after the expanding process.

After extending the second pressure-sensitive adhesive sheet 20 to increase the distance between the plurality of semiconductor chips CP to the distance D2, the surface protective sheet 40 is attached to the circuit surface W1 of the semiconductor chip CP. The surface protection sheet 40 includes a fourth base film 41 and a fourth pressure-sensitive adhesive layer 42. It is preferable that the surface protection sheet 40 is stuck so that the circuit surface W1 may be covered with the fourth pressure-sensitive adhesive layer 42.

When the second pressure-sensitive adhesive sheet 20 is peeled off after the surface protective sheet 40 is adhered, the back surfaces W3 of the plurality of semiconductor chips CP are exposed. It is preferable that the distance D2 between the plurality of semiconductor chips CP expanded in the expanding process is maintained even after the second pressure-sensitive adhesive sheet 20 is peeled off. When the energy ray polymerizable compound is blended in the second pressure-sensitive adhesive layer 22, the second pressure-sensitive adhesive layer 22 is irradiated with energy rays from the second base film 21 side, and the energy ray polymerizable compound is irradiated. It is preferable to peel the second pressure-sensitive adhesive sheet 20 after curing.

FIG. 6B shows a diagram for explaining a process of sealing a plurality of semiconductor chips CP held by the surface protection sheet 40.

The sealing body 3 is formed by covering the plurality of semiconductor chips CP with the sealing member 60 while leaving the circuit surface W1. The sealing member 60 is also filled between the plurality of semiconductor chips CP. Here, since the circuit surface W1 and the circuit W2 are covered by the surface protection sheet 40, it is possible to prevent the circuit surface W1 from being covered by the sealing member 60.

By the sealing process, a sealing body 3 in which a plurality of semiconductor chips CP separated by a predetermined distance are embedded in a sealing member is obtained. In the sealing step, the plurality of semiconductor chips CP are preferably covered with the sealing member 60 while the distance D2 is maintained.

When the surface protection sheet 40 is peeled after the sealing step, the surface 3S that has been in contact with the circuit surface W1 of the semiconductor chip CP and the surface protection sheet 40 of the sealing body 3 is exposed (see FIG. 3A). ).

[Rewiring layer forming step, connecting step with external terminal electrode, and second dicing step]
Subsequent to the sealing step, a rewiring layer forming step, a connection step with an external terminal electrode, and a second dicing step are performed. These steps can be performed in the same manner as in the manufacturing method according to the first aspect (see FIGS. 3B and 3C). Through these steps, FO-WLP is obtained.

[Modification]
In the FO-WLP manufacturing method according to the second aspect described above, some processes may be changed or some processes may be omitted. Such a modification will be described below.

As a first modification of the manufacturing method according to the second aspect, a step of peeling only the first pressure-sensitive adhesive sheet 10 may be performed following the step of attaching the second pressure-sensitive adhesive sheet 20. That is, in the second embodiment described above, when the first pressure-sensitive adhesive sheet 10 is peeled off, the cut protective sheet 30 is accompanied and peeled, whereas in the present modification, the protective sheet 30 is attached to the semiconductor chip CP. The first adhesive sheet 10 is peeled off while remaining on the circuit surface W1. By peeling off the first pressure-sensitive adhesive sheet 10, as shown in FIG. 7A, a plurality of semiconductor chips CP to which the cut protective sheet 30 is attached are stacked on the second pressure-sensitive adhesive sheet 20. Become.

Subsequently, as shown in FIG. 7B, the expanding process described above is performed. That is, the second adhesive sheet 20 is stretched in a state where the cut protective sheet 30 is attached to the circuit surface W1 of the semiconductor chip CP, and the space between the plurality of semiconductor chips CP is expanded to the distance D2.

After the expanding process, as shown in FIG. 7C, a process of sealing a plurality of semiconductor chips CP is performed. In the second aspect described above, the semiconductor chip CP is sealed on the surface protection sheet 40 as shown in FIG. 6B, whereas in this modification, as shown in FIG. On the second adhesive sheet 20, the semiconductor chip CP is sealed using the sealing member 60. Here, since the protective sheet 30 is adhered to the circuit surface W1, the surface protective sheet 40 may not be adhered, and the second adhesive sheet is adhered to the back surface W3 of the semiconductor chip CP. Can be sealed as it is. The sealing body 3 is formed by covering the plurality of semiconductor chips CP with the sealing member 60 while leaving the circuit surface W1. It is preferable that the surface 3S of the sealing body 3 and the circuit surface W1 of the semiconductor chip CP are the same surface.

After the sealing step, the protective sheet 30 and the second adhesive sheet 20 are peeled off. Then, the FO-WLP is obtained by performing the above-described rewiring layer forming step, connecting step with the external terminal electrode, and second dicing step.

Since the semiconductor processing sheet according to the present embodiment can be stretched greatly, it can be suitably used for applications where the interval between semiconductor chips needs to be greatly expanded as described above.

The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, when the semiconductor processing sheet has a configuration including a base material and a pressure-sensitive adhesive layer, another layer may be interposed between the base material and the pressure-sensitive adhesive layer.

Hereinafter, the present invention will be described more specifically with reference to examples and the like, but the scope of the present invention is not limited to these examples and the like.

[Example 1]
(1) Preparation of adhesive composition Acrylic copolymer obtained by reacting butyl acrylate / 2-hydroxyethyl acrylate = 85/15 (mass ratio), and 80 mol relative to 2-hydroxyethyl acrylate % Methacryloyloxyethyl isocyanate (MOI) was reacted to obtain an energy ray curable polymer. The energy ray curable polymer had a weight average molecular weight (Mw) of 600,000.

100 parts by mass of the obtained energy ray curable polymer, 3 parts by mass of 1-hydroxycyclohexyl phenyl ketone (product name “Irgacure 184”, manufactured by BASF) as a photopolymerization initiator, and tolylene diisocyanate as a crosslinking agent 0.45 parts by mass of a system cross-linking agent (manufactured by Tosoh Corporation, product name “Coronate L”) was mixed in a solvent to obtain an adhesive composition.

(2) Production of semiconductor processing sheet For the release surface of a release film (product name “SP-PET3811”, manufactured by Lintec Corporation) in which a silicone release agent layer is formed on one side of a polyethylene terephthalate (PET) film The pressure-sensitive adhesive composition was applied and dried by heating to form a pressure-sensitive adhesive layer having a thickness of 10 μm on the release film. After that, one side of a polyester polyurethane elastomer sheet (manufactured by Sea Dam Co., Ltd., product name “Higress DUS202”, thickness 50 μm) as a base material is bonded to the exposed surface of the pressure-sensitive adhesive layer. A sheet for semiconductor processing was obtained in a state where was stuck.

[Comparative Example 1]
By kneading 100 parts by weight of polyvinyl chloride resin (PVC, average degree of polymerization: 1050), 42 parts by weight of adipic acid polyester plasticizer and a small amount of stabilizer, and molding into a film using a calendar device A semiconductor processing sheet was produced in the same manner as in Example 1 except that the obtained vinyl chloride film having a thickness of 80 μm was used as a base material.

[Comparative Example 2]
A semiconductor processing sheet was produced in the same manner as in Example 1 except that a polypropylene film (PP, manufactured by Diaplus Film Co., Ltd., product name “LT01-06051”) having a thickness of 80 μm was used as a base material.

[Test Example 1] (Tensile test)
The semiconductor processing sheets produced in the examples and comparative examples were cut into 15 mm × 140 mm, and the release sheet was peeled off to obtain test pieces. About the said test piece, based on JISK7161: 2014 and JISK7127: 1999, the elongation at break and tensile elastic modulus in 23 degreeC were measured. Specifically, the test piece was set to a distance between chucks of 100 mm with a tensile tester (manufactured by Shimadzu Corporation, product name “Autograph AG-IS 500N”), and then subjected to a tensile test at a speed of 200 mm / min. The elongation at break (%) and the tensile modulus (MPa) were measured. The measurement was performed in both the flow direction (MD) during production of the substrate and the direction perpendicular to the flow direction (CD). The results are shown in Table 1.

[Test Example 2] (Measurement of 100% stress and restoration rate)
The semiconductor processing sheet obtained in the example or comparative example was cut into 150 mm × 15 mm, and the release sheet was peeled off to obtain a test piece. In addition, it cut | disconnected so that the flow direction (MD direction) at the time of manufacture of the sheet | seat for semiconductor processing might become the length direction of a test piece. Thereafter, both ends in the length direction of the test piece were fixed with a gripping tool of a tensile tester (manufactured by Shimazu Seisakusho, product name “Autograph AG-IS 50N”). At this time, the test piece was gripped with the gripping tool so that the length between the gripping tools was 100 mm. This length was defined as the length L0 (mm) between the initial grippers. And it pulled 100 mm in the length direction at a speed | rate of 200 mm / min, and the length between grips was 200 mm. The length obtained by subtracting the length L0 (mm) (that is, 100 mm) between the initial grippers from this length was defined as the extended length L1 (mm). The test force at this time was measured, and the 100% strength (N) in the tensile test was determined to obtain the 100% strength (N) in the MD direction. And 100% strength (MPa) of MD direction was calculated | required by dividing 100% intensity | strength (N) of MD direction by the cross-sectional area of a semiconductor processed sheet. Furthermore, after holding for 1 minute in a state where the length between the grips is 200 mm, the grips are returned at a speed of 200 mm / min until the length between the grips reaches L0 (mm). The length was maintained for 1 minute in a state of L0 (mm). Then, it pulled in the length direction at the speed | rate of 60 mm / min, and recorded the length between the holding tools when the tensile force showed 0.1 N / 15mm. A value obtained by subtracting the length L0 (mm) between the initial grippers from this length was defined as L2 (mm).

The values of L1 and L2 were applied to the following formula (I), and the restoration rate (%) was calculated. The results are shown in Table 1.
Restoration rate (%) = {1− (L2 ÷ L1)} × 100 (I)

Further, the semiconductor processing sheet obtained in the example or the comparative example was cut into 150 mm × 15 mm so that the direction (CD direction) perpendicular to the flow direction at the time of manufacture was the length direction of the test piece. The test piece obtained by peeling the release sheet was also measured for 100% strength (N) and 100% stress (MPa) in the same manner as described above, and 100% strength (N) and CD direction in the CD direction, respectively. 100% stress (MPa). The results are shown in Table 1. Furthermore, the ratio of 100% stress (MPa) in the MD direction to 100% stress (MPa) in the CD direction was calculated. The results are also shown in Table 1.

[Test Example 3] (Expand test)
The release sheet of dicing tape (product name “ADWILL D-675” manufactured by Lintec Corporation) is peeled off, and the exposed adhesive surface is divided into a ring frame and a 6-inch silicon mirror wafer (diameter: 150 mm, thickness: 350 μm, ground surface # 2000). Next, using a dicer (manufactured by Disco Corporation, product name “DFD-651”), the silicon mirror wafer was diced in a full cut under the following conditions. As a result, a plurality of individual silicon chips were obtained on the dicing tape. Thereafter, the dicing tape, using a UV irradiation device (manufactured by Lintec Corporation, product name "RAD-2000m / 12"), UV irradiation (illuminance: 120mW / cm ^2, the amount of light: 70mJ / cm ²⁾ was carried out .
・ Dicing blade: manufactured by Disco Corporation, product name “NBC-ZH205O 27HECC”
・ Rotation speed: 30,000 rpm
・ Height: 0.06mm
・ Cut speed: 60mm / sec
・ Chip size: 3mm × 3mm

Subsequently, the semiconductor processing sheet obtained in the example or the comparative example was cut into a square size of 210 mm × 210 mm. At this time, each side of the cut sheet was cut so as to be parallel or perpendicular to the MD direction of the substrate in the semiconductor processing sheet. Next, the release sheet was peeled off, and all of the silicon chips obtained by the dicing were transferred to the exposed adhesive surface. At this time, transfer was performed so that a group of silicon chips were located in the center of the semiconductor processing sheet. Further, the dicing line when the silicon wafer was separated into pieces was transferred so as to be parallel or perpendicular to each side of the semiconductor processing sheet.

Next, the semiconductor processing sheet on which the silicon chip was transferred was placed in an expanding apparatus (separating apparatus) capable of biaxial stretching. FIG. 8 shows a plan view for explaining the expanding apparatus 100. In FIG. 8, the X axis and the Y axis are orthogonal to each other. The positive direction of the X axis is the + X axis direction, the negative direction of the X axis is the −X axis direction, and the positive direction of the Y axis. Is the + Y axis direction, and the negative direction of the Y axis is the -Y axis direction. The semiconductor processing sheet 200 was installed in the expanding apparatus 100 so that each side was parallel to the X axis or the Y axis. As a result, the MD direction of the base material in the semiconductor processing sheet 200 is parallel to the X axis or the Y axis. In FIG. 8, the silicon chip is omitted.

As shown in FIG. 8, the expanding apparatus 100 includes five holding means 101 (20 holding means 101 in total) in each of the + X axis direction, the −X axis direction, the + Y axis direction, and the −Y axis direction. Of the five holding means 100 in each direction, the one located at both ends is the holding means 101A, the one located in the center is the holding means 101C, and the one located between the holding means 101A and the holding means 101C is the holding means. 101B. Each side of the semiconductor processing sheet 200 was held by these holding means 101.

Here, as shown in FIG. 8, one side of the semiconductor processing sheet 200 is 210 mm. The interval between the holding means 101 on each side is 40 mm. Further, the distance between the end portion (the apex of the sheet) on one side of the semiconductor processing sheet 200 and the holding means 101A closest to the end portion is 25 mm.

Subsequently, a plurality of tension applying means (not shown) corresponding to each of the holding means 101 were driven to move the holding means 101 independently of each other. At this time, the five holding units 101 that grip one side of the semiconductor processing sheet 200 on the + X-axis direction side were moved in the + X-axis direction at a stretching speed of 2.5 mm / sec for 40 seconds. At the same time, among these five holding means 101, the holding means 101A and the holding means 101B were moved in the direction away from the holding means 101C (that is, the + Y axis direction or the −Y axis direction). At this time, the holding means 101A was moved at a stretching speed: 2/3 of 2.5 mm / sec, and the holding means 101B was moved at a stretching speed: 1/3 of 2.5 mm / sec. The holding means 101C was not moved in the + Y axis direction and the −Y axis direction. Regarding the holding means 101 located on the three directions other than the + X-axis direction in the semiconductor processing sheet 200, the movement in each direction and the holding means 101A and the holding means 101B are moved from the holding means 101C in the same manner as the + X-axis direction. Moved away.

As a result of moving each holding means 101 as described above, the semiconductor processing sheet 200 is stretched by 100 mm each in the + X-axis direction and the −X-axis direction, and 100 mm each in the + Y-axis direction and the −Y-axis direction. It was stretched. That is, the semiconductor processing sheet 200 was stretched by 200 mm on each side. As a result, the length of each side of the stretched semiconductor processing sheet 200 was 410 mm.

About the semiconductor processing sheet 200 in the stretched state as described above, the presence or absence of breakage was evaluated based on the following criteria. The results are shown in Table 1.
○: The film was stretched satisfactorily without causing breakage.
X: Breakage occurred.

Further, for the semiconductor processing sheet 200 in which the evaluation of the presence or absence of breakage was “◯”, the outer diameter of the substantially circular shape composed of a plurality of silicon chips in the stretched state of the semiconductor processing sheet 200 ( The length corresponding to the outer diameter of the silicon wafer before dicing and stretching) was measured as the length corresponding to the wafer outer diameter (mm). The results are shown in Table 1.

Further, the measured length (mm) corresponding to the wafer outer diameter was applied to the following calculation formula (II) to calculate the chip interval (mm). The results are shown in Table 1.
Chip interval (mm) = {length corresponding to wafer outer diameter (mm) −150 mm (silicon wafer diameter)} ÷ 49 (number of dicing lines) (II)

In the above formula (II), the number of dicing lines is 49. When a silicon wafer having a diameter of 150 mm is diced into a chip size of 3 mm × 3 mm, the silicon wafer is in one direction and in a direction perpendicular to the direction. Dicing is performed at intervals of 3 mm, and each direction is divided into a maximum of 50, based on the fact that the number of dicing lines at that time is 49 in each direction.

As is clear from Table 1, the semiconductor processing sheets of the examples could be greatly stretched without breaking.

The semiconductor processing sheet according to the present invention is suitably used for manufacturing, for example, FO-WLP.

W ... Semiconductor wafer W1 ... Circuit surface W2 ... Circuit W3 ... Back surface W4 ... Internal terminal electrode W5 ... Groove W6 ... Back surface CP ... Semiconductor chip 1 ... Semiconductor package 3 ... Sealing body 4A ... First insulating layer 4B ... Second Insulating layer 5 ... Rewiring layer 5A ... External electrode pad 6 ... External terminal electrode 10 ... First adhesive sheet 11 ... First base film 12 ... First adhesive layer 20 ... Second adhesive sheet 21 ... First Second base film 22 ... second adhesive layer 30 ... protective sheet 40 ... surface protective sheet 41 ... fourth base film 42 ... fourth adhesive layer 50 ... grinder 60 ... sealing member 100 ... expanding

device

101, 101A, 101B, 101C ... Holding means 200 ... Semiconductor processing sheet

Claims

A semiconductor processing sheet comprising at least a base material,
The restoration rate of the semiconductor processing sheet is 70% or more and 100% or less,
In the test piece obtained by cutting the semiconductor processing sheet into 150 mm × 15 mm, the restoration rate is obtained by grasping both ends in the length direction with a gripping tool so that the length between the gripping tools is 100 mm, and then between the gripping tools. Is pulled at a speed of 200 mm / min until the length of the grip becomes 200 mm, held for 1 minute with the length between the grips extended to 200 mm, and then 200 mm / length until the length between the grips reaches 100 mm. Return to the length direction at a speed of min, hold for 1 minute with the length between the grippers returned to 100 mm, and then pull in the length direction at a speed of 60 mm / min. Measure the length between grips when showing 1N / 15mm, and subtract the length of 100mm between the initial grips from the length to make L2 (mm). When kicking the length obtained by subtracting the length of 100mm between the initial jaw from the length 200mm between jaws was L1 (mm), the following formula (I)
Restoration rate (%) = {1− (L2 ÷ L1)} × 100 (I)
A sheet for semiconductor processing, which is a value calculated from
A semiconductor processing sheet comprising at least a base material,
The ratio of the 100% stress of the semiconductor processing sheet measured in the MD direction of the substrate at 23 ° C. to the 100% stress of the semiconductor processing sheet measured in the CD direction of the substrate at 23 ° C. 0.8 or more and 1.2 or less,
The 100% stress is obtained by gripping both ends in the length direction with a gripping tool so that the length between the gripping tools becomes 100 mm in a test piece obtained by cutting the semiconductor processing sheet into 150 mm × 15 mm, and thereafter speed of 200 mm. It is a value obtained by dividing the measured value of the tensile force when it is pulled in the length direction at / min and the length between the grips becomes 200 mm by the cross-sectional area of the semiconductor processing sheet. Sheet for semiconductor processing.
A semiconductor processing sheet comprising at least a base material,
The tensile elastic modulus of the semiconductor processing sheet measured in the MD direction and the CD direction of the substrate at 23 ° C. is 10 MPa or more and 350 MPa or less,
100% stress of the semiconductor processing sheet measured in the MD direction and CD direction of the substrate at 23 ° C. is 3 MPa or more and 20 MPa or less, respectively.
The 100% stress is obtained by gripping both ends in the length direction with a gripping tool so that the length between the gripping tools becomes 100 mm in a test piece obtained by cutting the semiconductor processing sheet into 150 mm × 15 mm, and thereafter speed of 200 mm. It is a value obtained by dividing the measured value of the tensile force when the length between the grips becomes 200 mm by dividing the sectional area of the semiconductor processing sheet by pulling in the length direction at / min.
The semiconductor processing sheet, wherein the breaking elongation of the semiconductor processing sheet measured in the MD direction and the CD direction of the substrate at 23 ° C. is 100% or more, respectively.
The semiconductor processing sheet according to any one of claims 1 to 3, further comprising an adhesive layer laminated on at least one surface of the substrate.
The semiconductor processing sheet according to any one of claims 1 to 4, wherein the base material contains a thermoplastic elastomer.
The semiconductor processing sheet according to claim 5, wherein the thermoplastic elastomer is a urethane-based elastomer.
7. The semiconductor chip according to claim 1, wherein the semiconductor chip is used to increase a distance between adjacent semiconductor chips in a plurality of semiconductor chips stacked on one side of the semiconductor processing sheet to 200 μm or more and 6000 μm or less. The semiconductor processing sheet according to claim 1.
By stretching the semiconductor processing sheet by applying tension in the four directions of the X-axis direction, the -X-axis direction, the + Y-axis direction, and the -Y-axis direction on the X-axis and the Y-axis orthogonal to each other, The semiconductor processing sheet according to any one of claims 1 to 7, wherein the semiconductor processing sheet is used to increase a distance between a plurality of semiconductor chips laminated on one side.
Providing a plurality of individual semiconductor chips on one side of the adhesive sheet;
9. The method according to claim 1, wherein the pressure-sensitive adhesive sheet is used as the pressure-sensitive adhesive sheet in a method of manufacturing a semiconductor device comprising a step of extending the pressure-sensitive adhesive sheet and widening the interval between the plurality of semiconductor chips. The semiconductor processing sheet according to 1.
10. The semiconductor processing sheet according to claim 1, wherein the semiconductor processing sheet is used for manufacturing a fan-out type semiconductor wafer level package.